(1) Field of the Invention
The present invention relates to a vehicle theft protecting system for detecting an action such as stealing a vehicle and thieving goods in a vehicle, protecting from such an action, and effecting a countermeasure against such an action. Further, the present invention relates to a vehicle-onboard device mounted on a vehicle and management station at a parking area for vehicle theft protection. Furthermore, the present invention relates to a method of protecting a vehicle from theft and a related program used for such a system.
(2) Description of the Related Art
At parking areas where the public is allowed to enter, there are dangers of encountering stealing a vehicle and theft in a vehicle. Further, even at a parking area where only limited persons (contract customers) are allowed to enter, there are also dangers of encountering stealing a vehicle and theft in a vehicle unless a protection system is provided to prevent unknown persons from entering such areas. In view of the above-described circumstances, systems have been required to provide a high security capable of protecting vehicles at a parking area from vehicle theft and theft in a vehicle. Thus, various vehicle theft protection systems have been proposed.
For example, Japan se Laid-Open patent application publication No. 2002-216256 discloses a security system for parking areas in which a vehicle security system mounted on a vehicle cooperates with a ground security system installed at the parking area to protect the vehicle from theft. According to this security system for parking areas, when a vehicle with the vehicle security system is parked in a parking area with the ground security system, a wireless link is formed therebetween. In this condition when an error, for example, a strong vibration, occurs, the vehicle security system detects this and transmits an error detection signal to the ground security system through wireless communication using the wireless link. On reception of the error detection signal, the ground security system informs a mobile communication terminal, for example, a portable telephone, previously registered as an emergency notified station or starts taking an image of the vehicle with a monitor camera.
Further, Japanese Laid-Open patent application publication No. 2002-342897 discloses a parking area managing system. FIG. 1 illustrates a general structure of this parking area management system.
In FIG. 1, the parking area management system comprises vehicle-onboard communication unit 35 mounted on a vehicle, gate unit 33, center control unit 34, and ground communication unit 36 installed in a parking area. Center control unit 34, gate unit 33, and ground communication unit 36 are communicable with each other.
Vehicle-onboard communication unit 35 comprises card reader 21, card attachment/detachment detection unit 22, theft monitor setting unit 23, device ID unit 25, wireless communication unit 26, and control unit 24 for controlling operations of these units. The card reader 21 reads individual information from ID card 20 and transmits it to control unit 24. Card attachment/detachment detection unit 22 detects attachment and detachment of ID card 20 in card reader 21 and informs control unit 24 of the detection result. Theft monitor setting unit 23 is a switch for setting a theft monitor function operative or inoperative. A user can set or release the theft monitor function by turning on and off this switch. Device ID unit 25 stores an identification code of the vehicle-onboard communication unit 35. Wireless communication unit 26 effects wireless communication with ground communication unit 36 through antenna 27.
Ground communication unit 36 comprises network communication unit 28, ID collation unit 29, wireless communication unit 31, and control unit 30 for controlling operations of these units. Network communication unit 28 provides mutual communication with center control unit 34. Wireless communication unit 31 effects wireless communication with vehicle-onboard communication unit 35 through antenna 32. ID collation unit 29 collates the identification code of device ID unit 25 transmitted from vehicle-onboard communication unit 35.
In the above-described parking area management system, it is assumed that a user parks a car with vehicle-onboard communication unit 35 in a parking area on which ground communication unit 36 is installed, wherein ID card 20 is being attached to card reader 21 of vehicle-onboard communication unit 35. When the car is parked, communication is established between ground communication unit 36 and vehicle-onboard communication unit 35 mounted on the parked car. Then, an individual ID read from ID card 20 and an identification code of device ID unit 25 are transmitted from vehicle-onboard communication unit 35 to ground communication unit 36. Ground communication unit 36 transmits th received individual ID and identification code of device ID unit 25 by network communication unit 28 to center control unit 34 to be used for the monitoring operation.
Next, the user sets theft monitor setting unit 23 to operate the theft monitor function. When the user pulls out ID card 20 from card reader 21, vehicle-onboard communication unit 35 transmits the notice of pulling out ID card 20 to ground communication unit 36. The ground communication unit 36 starts vehicle theft monitoring for the parked car from when ID card 20 is pulled out. This vehicle theft monitoring can be released by turning off theft monitor setting unit 23 after attaching ID card 20 to card reader 21.
On start of vehicle theft monitor, vehicle-onboard communication unit 35 and ground communication unit 36 start periodical communication. After start of communication, if communication between vehicle-onboard communication unit 35 and ground communication unit 36 is stopped due to movement of the car or damage of vehicle-onboard communication unit 35, ground communication unit 36 detects this condition as theft of the car.
Further, if there is trial to continue communication with ground communication unit 36 using another vehicle-onboard communication unit that is different from vehicle-onboard communication unit 35, disagreement occurs in verification of device ID at ID collation unit 29. Ground communication unit 36 detects this condition as theft of the car.
Furthermore, if another ID card, which is different from ID card 20, is used to release the vehicle theft monitoring, disagreement occurs in verification of individual ID at ID collation unit 29. Ground communication unit 36 detects this condition as th ft of the car.
However, the above-described conventional theft protection systems have problems as follows:
In the security system for a parking area disclosed in Japanese Laid-Open patent application publication No. 2002-216256, theft actions involving the car are detected only on the side of the vehicle security system. Thus, if the function of the vehicle security system is stopped, theft of the car cannot be prevented.
Further, the notice of error occurrence by the security system for a parking area cannot be performed unless the error detection signal is received from the vehicle security system through wireless communication. In addition, there is no countermeasure against obstruction to wireless link formed between systems. Thus, interference in transmission of the error detection signal from the vehicle security system disables the vehicle theft protection.
In the parking area managing system disclosed in Japanese Laid-Open patent application publication No. 2002-342897, interruption of communication is detected only by the side of the ground communication unit, and transmission of theft information is performed one-way from vehicle-onboard communication unit to the ground communication unit, so that the vehicle-onboard communication unit cannot detect stopping of the function of the ground communication unit.
In addition, although the ground communication unit side determines whether the vehicle-onboard communication unit is a right one or not, the vehicle-onboard communication side does not determine whether the ground communication vehicle is a right one or not. Accordingly, for example, if the function of the right ground communication unit is stopped to operate a dummy ground communication unit capable of normally responding to the vehicle-onboard communication before the user parks a car in the parking area, the vehicle-onboard communication unit cannot detect that the communication partner is a dummy. In this case, because the dummy ground communication unit is disconnected from the center control unit, the center control unit side cannot interrupt the communication and detect theft by ID collation. Thus, there is a danger of vehicle theft by a pretense to the ground communication unit.
Further, because the communication between the ground communication unit and the vehicle-onboard communication unit is not subjected to encryption, a third party can tap the individual ID or the identification code of the device ID. Thus, for example, if the function of the regular vehicle-onboard communication unit is stopped and as well as a dummy vehicle-onboard communication unit is operated which is capable of transmitting the individual ID and the identification code of the device ID obtained by tapping, the ground communication unit presumes the dummy vehicle-onboard communication unit to be the right one, so that theft of the car cannot be detected. As described above, there is a danger of vehicle theft by pretense to the vehicle-onboard communication unit.